[PATCH] net/bonding: set initial value of descriptor count alignment

[humin (Q)]

Acked-by: Min Hu (Connor) <humin29 at huawei.com>

在 2022/10/31 21:17, Ivan Malov 写道:
> The driver had once been broken by patch [1] looking to have
> a non-zero "nb_max" value in a use case not involving adding
> any back-end ports. That was addressed afterwards ([2]). But,
> as per report [3], similar test cases exist which attempt to
> setup Rx queues on a void bond before attaching any back-end
> ports. Rx queue setup, in turn, involves device info get API
> invocation, and one of the checks on received data causes an
> exception (division by zero). The "nb_align" value is indeed
> zero at that time, but, as explained in [2], such test cases
> are totally incorrect since a bond device must have at least
> one back-end port plugged before any ethdev APIs can be used.
>
> Once again, to avoid any problems with fixing the test cases,
> this patch adjusts the bond PMD itself to workaround the bug.
>
> [1] commit 5be3b40fea60 ("net/bonding: fix values of descriptor limits")
> [2] commit d03c0e83cc00 ("net/bonding: fix descriptor limit reporting")
> [3] https://bugs.dpdk.org/show_bug.cgi?id=1118
>
> Fixes: d03c0e83cc00 ("net/bonding: fix descriptor limit reporting")
> Cc: stable at dpdk.org
>
> Signed-off-by: Ivan Malov <ivan.malov at oktetlabs.ru>
> Reviewed-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
> ---
>   drivers/net/bonding/rte_eth_bond_pmd.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/net/bonding/rte_eth_bond_pmd.c b/drivers/net/bonding/rte_eth_bond_pmd.c
> index dc74852137..145cb7099f 100644
> --- a/drivers/net/bonding/rte_eth_bond_pmd.c
> +++ b/drivers/net/bonding/rte_eth_bond_pmd.c
> @@ -3426,6 +3426,8 @@ bond_alloc(struct rte_vdev_device *dev, uint8_t mode)
>   	 */
>   	internals->rx_desc_lim.nb_max = UINT16_MAX;
>   	internals->tx_desc_lim.nb_max = UINT16_MAX;
> +	internals->rx_desc_lim.nb_align = 1;
> +	internals->tx_desc_lim.nb_align = 1;
>   
>   	memset(internals->active_slaves, 0, sizeof(internals->active_slaves));
>   	memset(internals->slaves, 0, sizeof(internals->slaves));